This proposal describes a 5-year training program for the development of an academic career in Endocrinology. The principal investigator has completed the required clinical training in Endocrinology and now will expand upon her scientific skills through a unique integration of interdepartmental resources. This program will promote the command of signal transduction biology as applied to the nervous system. Morris J. Birnbaum, M.D., Ph.D. will mentor the principal investigator's scientific development. Dr. Birnbaurn is a recognized leader in the field of signal transduction. He is a professor of Medicine and has trained numerous postdoctoral fellows and graduate students. To enhance the training, the program will enlist the expertise of Virginia M.-Y. Lee, Ph.D. Dr. Lee is the Director for the Center for Neurodegenerative Disease Research and is a leader in the field of Alzheimer's disease and dementia research. In addition, an advisory committee of highly regarded medical scientists will provide scientific and career advice. Research will focus on the signal transduction pathways regulating neuronal size. The specific aims include: 1) Determining the cellular mechanism by which Akt3 regulates brain size, 2) Determining the physiological importance of other isoforms of Akt in brain, and 3) Determining the molecular mechanism by which Akt controls brain size. This will be the first detailed analysis of isoform specific effects of Akt in neurons. In addition, this work will provide a better understanding of the signal transduction pathway regulated by Akt, a pathway altered in schizophrenia. The Medicine Department of the University of Pennsylvania provides an ideal setting for training physician scientists by incorporating expertise from diverse resources into customized programs. Such an environment maximizes the potential for the principal investigator to establish a scientific niche from which an academic career can be constructed.